The production of concrete and other similar composite materials that include components such as sand, aggregate, gravel, cement, fly ash, and/or other granular (including powdered) ingredients may be aided by providing controllable feed bins containing each of the necessary ingredients. The ingredients are distributed from the bins into a receiving bin or onto a conveyor belt that carries the ingredients to a mixing device or chamber. Alternatively, the bins may deliver the various ingredients directly into a mixing device.
Evolving applications for concrete and similar composite materials require increased precision in terms of the amount of various ingredients that are needed to achieve the desired composition and resulting qualities of the final composite material. Hand measuring or adjustment of amounts is possible but inefficient. Thus, there is a need for precise control of the amount of material distributed from a bin in order to achieve the desired composition.
To achieve precise distribution of materials from bins, one approach is to provide a bin having a large opening and a small opening. However, past arrangements having a large and a small opening have created the two openings by equipping the bins with two movable bin gates and therefore require a second, additional control mechanism for the second gate. Such an arrangement is described in U.S. Pat. No. 4,278,290 (Oory et al.). One drawback of such arrangement is the expense of specially equipping each bin with multiple gates and control mechanisms. An additional drawback to such arrangements is that certain types of material tend to get jammed or stuck inside the bin when only a small output opening is provided. This limits the types of material that may be dispensed by the bin.
Thus, there is a need for a bin gate assembly that enables increased precision in the control of the output quantities provided from the bin opening while minimizing the need for additional equipment and mitigating the jamming/sticking issues of past arrangements.